His novel “Forrest Gump” was reissued in a 25th anniversary edition, and now his sixteenth book, his third study of a Civil War battle, has been published. This is a highly detailed narrative and the reader had better want to learn a lot about the Battle of Shiloh, April 6th and 7th, 1862.

The battle came less than one year into the war. In Virginia there had been several big battles, especially First and Second Bull Run, but there had yet to be a meeting of great armies in the West, the territory from the Appalachians to the Mississippi.

Shiloh would be that battle, and the savagery and cost of that battle would change minds North and South. The war would not be over by that Christmas or the next or the next. The South learned the North would fight, and the Yankee generals, specifically Grant and Sherman, determined the South could be subdued only by total “conquest and subjugation.”

This volume is carefully, minutely, researched. Groom has amassed a veritable Civil War reference library, so some of this material he was already very familiar with. He gives very useful biographical sketches of characters like U. S. Grant, William Tecumseh Sherman, P.G.T. Beauregard and many of the other players. He also makes use of a half dozen different personal diaries by such figures as Ambrose Bierce, who would become a famous writer, Henry Morton Stanley, who would later “find” Dr. Livingston in Africa, and observers like young Elsie Duncan or Josie Underwood, who lived near the battle site.

Groom summarizes how the war had gone to this point, April of 1862, and how the major players had arrived there.

After a short and lucid summary of how Grant took Fort Henry and Fort Donelson, both in Tennessee, he gets to the main subject.

The site of the battle was itself a savage landscape, torn by ravines, crisscrossed by swollen creeks and wild tangles of woods devastated by tornadoes.

The Union Army was on the west bank of the Tennessee River and might have built up a good defensive position. But they did not.

In those days, Groom tells us, military intelligence was an oxymoron; it was not considered quite cricket to spy on your enemy, so the Union forces did not know how many rebels there were or where they were.

When the Southern forces attacked, the Union forces retreated and fortunately for them, there were some natural defensive positions to fight from. They halted the rebel advance at a sunken road and from different patches of woods on the north side of open fields.

As one always reads in Civil War histories, infantry charged bravely across open fields and were killed by the thousands, by artillery and quick-loading rifles.

The courage and the sacrifice were simply unbelievable.

The landscape was American, rough. The technology was advanced. The tactics were 50 years out of date, Napoleonic. The result was slaughter. Civil War casualties adjusted to today’s population would be 50 million, with 10 million dead. (Fifty-eight thousand Americans died in ten years in Vietnam.) Not much changed in the next 50 years either. At The Battle of the Somme, on July 1, 1916, the British lost 21,000 soldiers in one day, really in one hour.

At Shiloh, in two days, of the 100,000 present, there were 24,000 casualties, more than the American Revolution, the War of 1812 and the Mexican War COMBINED. On each side, about 1,700 were killed.

As had been the case at Bull Run and elsewhere, generals at Shiloh, first Beauregard one day and then Grant the next, were roundly criticized for not following up on success and finishing the enemy off: the so-called “Lost Opportunity.”

Groom explains, as I have not seen it explained before, how extremely difficult this would have been: “The physical exertion associated with rushing forward, crawling, dodging bullets, and even hand-to-hand fighting is nothing compared to the toll exerted by the mental exhaustion of battle. The terror, exhilaration, horror, and revulsion of just a few minutes in combat—to say nothing of a full day’s worth of it—overtaxes the body’s adrenaline and drastically drains the soldier of energy.”

Even if the general orders one more charge, he very likely isn’t going to get it.